Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered and the description correctly does not contradict it. The one piece of added behavioral context is that the phone must be the one supplied at order time, implying an identity-verification gate. It says nothing about what happens when the pair does not match, or what the status response contains.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

A single sentence, front-loaded with the resource and followed by the two lookup keys. Every clause earns its place and there is no filler or repetition beyond the useful example.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a two-parameter read-only lookup with full schema coverage and annotations, the essentials are present. However, there is no output schema, so the definition offers no indication of what a status response includes (status stages, delivery state, totals) or how failures are surfaced. An agent can call it but cannot anticipate the result shape.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, and both parameters carry their own descriptions plus a pattern and an example, so the description adds little beyond restating the lookup keys. The example order ID in the description duplicates the schema's own example verbatim. Baseline 3 applies when the schema does the heavy lifting.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description names a specific verb-and-resource pair: retrieving order status ('Статус заказа') keyed by order number and phone, with a concrete example order ID. It clearly distinguishes itself from siblings like create_order or delivery_quote by being a read-only lookup. It stops short of explicitly contrasting itself with any named alternative, which keeps it out of 5 territory.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Usage is implied rather than stated: an agent infers this is the tool for checking an existing order when it holds the order number and the phone used at purchase. There is no explicit when-to-use, when-not-to-use, or named alternative for related tasks such as creating an order or quoting delivery. The prerequisite (both identifiers required) is only implicit in the sentence structure.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.